Decorative glass shade.



PATENTED MAY 22, 1906.

'No. 821,308 I 0. A. MYGATT. DECORATIVE GLASS SHADE.

APPLICATION FILED DEG. 21, 1904 2 SHEETS-SHEET 1.

. attovwug Nb. 821,308. PATENTED MAY 22, 1906.

0. A. MYGATT, DECORATIVE GLASS SHADE.

APPLICATION FILED DEC. 21, 1904 v 2 SHEETS-SHEET 2.

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in the drawings.

, irn'rrnn s 'ra'rns PATENT carton OTXS A. MYGATT, OF NEW YORK, 'N. Y.

DEQQRATEVE GILAS$ SHADE Specification of Letters Patent.

Patented may 22, 1906.

Application filed December 21, 1904:. Serial No. 237,838.

This invention relates to decorative glass.

shades for artificial lights.

The object of the invention is to produce a globe or shade for lamps, gas-burners, electrio lights, &c., which shall be decorative in appearance and shall have the advantage of directing a large part of the li lit-rays, which are generally lost, into use I position by changing thedirection of many or most of the light-rays escaping from a part, generallythe upper part, of the surface of the shade.

My invention consists in the construction of shades or globes for lamps in a manner to largely combine the illuminating excellence -f prismatic shades or globes with the ornamental features of decoration, many of which have been separately used heretofore.

In carrying out my invention I availmyself of certain principles or laws of optics which are ossibly understood by experts, but which Fain unable to find briefly stated in text books and which -I will therefore state herein, referring to certain diagrams shown Figure 1 is a diagram illustrating the i course of light-rays under certain condltions in relation to plane glass. Fig. 2 is a dia ram illustrating such rays under other con itions in relationto plane lass. Figs-3 and 4 are diagrams illustrating t e course of lightrays on entering and emerging from certain forms of lass risms. Fig. 5 is a view of a glass sha e wit 1 internal decoration, the latter being indicated by dotted lines. Fi 6 is a sectional view of a art of the same. Fig. 7 is a section of a modification. Fig. 8 is a section of a globe embodying substantiall the same principles as the receding. Fig. 9 illustrates a artial elevation and partial section of a glbbe having external prisms on its upper portion and a frosted surface on its lower portion and internal decorations throughout. Fig. 10 is a partial elevation and partial section of an open-mouthed reflector having external radial reflectingprisms and internal decoration. Fig.11 is a similar view of a modification.

In glass globes and shades for artificiallights other than prismatic globes and shades the object is generally to artially obscure the light-rays, so that theys all not be so dazzling and harmful to the eyesi ht. The lightrays generally pass through t e substance of the g obe or shade without much deviation,

but with a partial obscurationduc to a tint.

in the glass frosting its surface, flutings, corrugations, 0. Such shades have been decorated in various manners-as, for instance, by painting usually in semitransparent colorsagain, by the production of ornamental figures on the glass, generally on the exterior thereof, as this surface is easier to be operated on.- Again, such globes and shades have been decorated by the addition of separate pieces, such as jewels or panels,inserted into, cemented on, or otherwise attached to the shades .or globes. Many other styles of decoration for such articles are known; but as a rule no attention has been paid to the direction of the li ht-rays which pass through the decorated lobes or shades. (For convenience I will hereinafter designate all such articles as shades.) I have heretofore manufactured and sold many thousands or glass shades which were 0 ternally covered with prisms, which prism dirent the li htrays in calculated directions. Many of t see are also internall covered with prismswhich break up and iffuse the lightrays.- An

objection frequently made to such shades is that while they are useful as directing the light-rays to the desired field of illuminatlon they are objectionable to many people because of their sameness of appearlight-rays strikin such surface in going from the air into the g ass; but this same surface becomes an excellent reflector to light-raysstriking its surface from inside the glass. Thus in Fig. 1, AB represents one surface of a polished piece of lane glass, and A B the ot or surface. Lig t-rays from P, perpendicular to the faceA B, will pass through the lass with little obstruction in the direction there being very little reflection and this penetration continues it the ends be ZIO - penetrate more or less; but at Y-tha't is,

forty-five de rees from the perpendicular light-rays-wiIl be almost totally reflected 1n the direction Y. Thus the second surface of the glass, rather than the first, is the effectpractically inert or neutral.

ive reflecting-surface. No shade can increase the amount of light; but by directing light-rays, which would otherwise escape to a field ofusefulness, the shade can be made to increase the effective amount of light from a lamp very materially. Rays generally lost are usually upward rays. Prism-glass shades, which either deflect or reflect such rays, generally depend on the external prisms to-give direction to the rays, and interior prisms for softening or diffusing the rays. In Fig 3, A B are supposed to represent the interior surface of 'a glass shade provided with prisms D on its outer surface. A light-ray from P passes through the glass and is reflected on the surface C D in the direction P The other surfaces than the surface C D are considered practically neutral or negligible. The surface 0 D acts just as well as a reflector when it. is covered'with dust as when clean. The innersurface A B of the shade and the under surface D E of the prism will not accumulate dust to the same extent as the surface 0 D, and a shade provided with such prisms can be kept in good Working condition with little care in the way of cleaning. In Fig. 4 the externaldouble-reflecting prisms C D E on a shade are caused to twice reflect the light-ray, which ray,- progressing from P, returns to the inside of the shade in the direction P the surface A B being 7 In this case also a layer of dust on the external prisms \does no harm as far as the reflection of light is concerned. Availing myself of these laws, facts, and discoveries, I construct decorative shades having substantially all the advantagesof light-control of the prismatic shades heretofore constructed, with the addition of hi h decorative adaptability.

n Fig. 5 I show ashade having its external surface covered with sin le-reflecting prisms 1. These prisms are al alike or of varied form, asmay be desirable, to direct the lightrays which pass through the glass in any desireddirection outside, such prisms being well known in the art. On the inside of the shade I produce, either in cameo or intaglio, ornamental forms or figuresas, for instance, a'star 2. This figure will break up the-mo- "notony of the external appearance, as it will .show through the lass and Will to some extent break up the ight-rays passing through mined directions.

ive operation 0 it, but not with uniformity. The decorative form seen from without will present the peculiar silvery appearance which decorations impressed into or raised from the reverse surface of lass usually show, modified to some extent by the external prisms. The direc tion or distribution of the light-rays by the external prisms will be modified by reason of the raised or depressed decorative form on the interior of the shade. The light-rays which strike the projecting form on the inte-' rior of the shade are naturally more obscured by a thick body of glass than by a thin one. Besides this, many of these rays are diverted so that. they strike the external prisms at different angles from what they would otherwise do, these diverted rays being given, in many instances, a new quality as well as a new direction. The result is that a shade which is externally covered with light-directing prisms will have a very different light:

rupts light r ays, but may be used for some purposes.

As the exterior of the shade is entirely covered with prisms, the great majority of the rays'which ass through the shade must recelve their al direction from such risms. The rays are therefore concentrate or focused, if concentration is desired, at such distance as the prismatic construction determines At the same time the decoration of the interior-of the shade may be as complete and as varied as if there were no prismatic surface whatever. As has been shown, the reflective eflect of the interior of the shade is much less than the exterior, and therefore but,

little loss of light will be caused by this i-nte-' rior decoration.

' The decorative forms or surfaces on the interior of the shade may be produced by molding or by cuttin engraving, or other well known manner 0' ornamentation.

In Fig. 9 1 illustrate the prinoi le of internal decoration as applied to a g obe having external circumferential lightdistributing prisms- Such prisms each re resent a number of outer plane surfaces ca culated to di-. rect the majority of the light-rays in deter' The rays emerge from the lower faces of these prisms, and acoating of dust on their to s does not prevent the efiectf lshe prisms. The lower outer surface of the globe is ground or frosted. The frosting acts as a light-radiating surface. The interior of the globe is decorated with do not prevent the li any ornamental forms desirable, asindicated These show through the prisms, but

at s e.

ht distribution by the prisms to any materia extent, although they change the character Being inside the globe the decorativefigures do not accumulate dust to any great extent. In Figs. 10 and 11 the sameprinciple is applied to prismatic glass reflectors. The external radial prisinsreflect the light down-i wise smooth inner surface of the reflector.

the decorations are visible;

The decorations may consist in words or lettering,'as well as in other forms. Theireffect is to break up light-rays to such extent that but they do not prevent the reflection by the prisms to any considerable extent.

From the foregoing it will appear that decorative shades made according to my'invention have substantially all the decorative effect of" any decorative shades heretofore made and have, in addition, the practical value of scientifically-constructed prismatic shades in the direction of a large proportion of the light-rays in determined directions, or,

' if the shade be considered as a'prismatic shade, it has nearly all the advantages of prismatic shades heretofore constructed or the ties of the best of such distribution i "glass havin Idirection and distributidhirpfifli t-rays, but

slightly modified by internal decoration, and

has, as far as maybe, the dust-'prdof 'quahrismatic construction w th substantialy as ullgcapacity for decoratmn as old forms of decorative shades.

, What I claim is- 1. A shade composed of single piece of outer surface substantially covered with light-directing prisms, and havingits general y smooth inner surface provided W1th figures hich are .out of the general surface level, which figures change the direction of many of the light rays passing through them toward the said prisms.

2. A shade composed of a'singl e piece of its outer surface substantially covered wit light directing prisms, and its inner surface generally smooth except as to certain decorative forms varying the general inner surface level to a greater extent in some glass having its parts than in other parts, whereby certain rays of light .passing through such rms are acted on to a greater extent than other ra s.

3. A shade composed of glass provide externally with light-directing prisms, and hav ing its interior generally smooth,,but having variations from the general level roducing forms which divert certain of the ight-rays from their normal direction toward said prisms, whereby the action of the prisms is also modified.

In testimony whereof I afiixmysignature in presence of two witnesses. I

- OTIS A. MYGAT'I.

Witnesses:

A. A.ERNsT, H. E. NASQN. 

